The present invention relates to an image forming apparatus including a plurality of exit trays.
Some image forming apparatuses include a plurality of exit trays. When such an image forming apparatus is shared among a plurality of users, one exit tray is loaded with various types of sheets in some cases, thus degrading sheet-type consistency and load efficiency.
Thus, a technique has been developed to switch an exit tray for outputting paper into another one when a sheet type is changed from the immediately preceding printing, thereby preventing different types of sheets from being mixed-loading on one exit tray (see Patent Document 1: Japanese Unexamined Patent Application Publication No. 2004-238187).
The technique disclosed in Patent Document 1, however, is not designed with consideration given to the number of sheets printed in the past by sheet type and the number of sheets stackable on each exit tray (hereinafter called sheet stack capacity), thus failing to output sheets effectively in some cases and so degrading sheet-type consistency and load efficiency.
In view of the above-stated problems, it is an object of the present invention to provide an image forming apparatus that can improve sheet-type consistency and load efficiency for trays.